Apparatus for scum removal



Nov. 23, 1965 R. P. MOORE APPARATUS FOR SCUM REMOVAL 2 Sheets-Sheet 1Filed Aug. 28, 1962 9% Wm mm mm,

AIM-Wm flail/mo Mame:

Nov. 23, 1965 R. P. MOORE APPARATUS FOR SCUM REMOVAL 2 Sheets-Sheet 2Filed Aug. 28, 1962 United States Patent 3,219,189 APPARATUS FOR SCUMREMOVAL Richard P. Moore, Argosy House, Spilsbury St., Germiston,Transvaal, Republic of South Africa Filed Aug. 28, 1962, Ser. No.219,877

Claims priority, application Republic of South Africa,

Aug. 29, 1961, R 1,311/61 2 Claims. (Cl. 210-195) moving parts, butsuffers from the disadvantage that it is difiicult to collect and retainthe scum in a concentrated area and further to move it along the bladeto the withdrawal point, and unless concentrated, liquid loss with scumwithdrawal is excessive.

An object of the invention is to provide a simplified scum removalsystem, in which the shortcomings of the abovementioned systems areconsiderably minimized and the scum is positively collected in aconcentrated area.

According to the present invention apparatus for removing scum from atank includes a blade on the surface of the liquid in the tank, jetsadapted to urge the scum to collect at the blade and to be forcedthrough an opening in the tank to a second tank, draw-0E means for thescum in the second tank and a passage from the second tank, below theopening, to the first tank.

In this apparatus, liquid is returned from the second tank to the first,while the scum collecting in the second tank is withdrawn. The passagefrom the second tank to the first is located at sufficient depth toensure that the scum cannot pass back again into the first tank.

Further according to the invention an induced flow is provided from thesurface of the liquid in the first tank through the opening to thesecond tank. This flow may be provided by means of a jet located at orin the openmg.

Still further according to the invention jets are provided along thelength of the blade. Thus, the front side of the blade is provided withjets spaced apart and adapted to motivate the scum in a substantiallycircular movement to the rear of the blade. Additional jets may beprovided on the rear of the blade and directed parallel thereto to forcethe scum into the opening to the second tank. An additional jet or jetsmay be located in the opening further to urge the scum into the secondtank.

According still further to the invention, the outer extremity of theblade is provided with a float.

Removal of the scum from the second tank may be eflfected by means of asmall Weir or the like or may be removed manually by skimming .or thelike or automatically by a suitably controlled gate or scoop.

It will be appreciated that the scum may be readily concentrated to aconsiderable degree in the second tank, and this prevents it fromdispersing, so that its removal is effected very economically with amaximum solids to water ratio.

It will also be realized that the second tank may serve a number of maintanks; it may also be located inside a settling tank or the like.

An embodiment of the invention is described below with reference to theaccompanying drawings, in which FIGURE 1 is a sectional side view ofapparatus according to the invention, and is a vertical section alongthe line 1-1 of FIGURE 2,

FIGURE 2 is a plan view of the apparatus, and

FIGURE 3 is a fragmentary perspective view of a blade, showing also theopening from the first tank into the second tank.

In the figures a settling tank 10 has an inlet 12 for liquid to besettled and an outlet 14 for withdrawal of the sludge which settles tothe bottom.

Adjacent the tank 10 is a second tank or pocket 16 which communicateswith the tank 10 through an opening 18 and also through a passage 20located at a lower level than opening 18. Reference 22 is an observationplatform.

A blade 24 is fixed at the opening 18 and extends along the surface ofthe liquid in tank 10. A float 26 is provided at the outer extremity ofthe blade 24. Preferably the blade should be three-quarters submerged.

Jets 28 are provided along the front surface of the blade 24. The angleswhich these jets make with the blade are chosen to induce the scumaround the surface of the liquid as indicated by arrows 30. The scumtherefore moves around to the rear or collecting surface of the blade,which is provided with jets 32, parallel to the blade and which urge thecollected scum along the blade through the opening 18. A jet 34 islocated in the opening to assist the flow of scum into the second tank16.

Jets 28, 32 and 34 may all be served by pipe 36 which communicates witha suitable source of liquid.

A scum board 38 and channel 40 are also provided.

The scum together with a quantity of liquid passes through the opening18 into tank 16, which has an outlet 42 for withdrawing the concentratedscum. Liquid reenters tank 10 through passage 20.

I claim:

1. In a tank having side walls and an opening in a said side wall forthe discharge of scum floating on the surface of liquid in the tank; theimprovement comprising blade means extending from adjacent said sidewall and adjacent said opening a substantial distance across the tankand being partially submerged in the liquid in the tank, jets on oneside of the blade means and directed away from the blade means therebyto move scum toward the opposite side of the blade means, and jets onsaid opposite side of the blade means parallel thereto and directedtoward said opening to move scum toward said opening.

2. Apparatus as claimed in claim 1, and a second tank, said openingcommunicating between the said first-named tank and said second tank,draw-off means for the scum in the second tank, and means defining apassage from the second tank, below said opening, into the first tank.

References Cited by the Examiner UNITED STATES PATENTS 838,626 12/1906Kirby 210-221 X 2,090,384 8/1937 Durdin 210-197 2,095,394 10/ 1937Morehead 210242 2,975,791 3/1961 Pansini 210169 X 3,152,076 10/ 1964Kreutzer 2l0-242 X REUBEN FRIEDMAN, Primary Examiner. ROBERT E. BURNETT,Examiner.

1. IN A TANK HAVING SIDE WALLS AND AN OPENING IN A SAID SIDE WALL FORTHE DISCHARGE OF SCUM FLOATING ON THE SURFACE OF LIQUID IN THE TANK; THEIMPROVEMENT COMPRISING BLADE MEANS EXTENDING FROM ADJACENT SAID SIDEWALL AND ADJACENT SAID OPENING A SUBSTANTIAL DISTANCE ACROSS THE TANKAND BEING PARTIALLY SUBMERGED IN THE LIQUID IN T HE TANK, JETS ON ONESIDE OF THE BLADE MEANS AND DIRECTED AWAY FROM THE BLADE MEANS THEREBYTO MOVE SCUM TOWARD THE OPPOSITE SIDE OF THE BLADE MEANS, AND JETS ONSAID OPPOSITE SIDE OF THE BLADE MEANS PARALLEL THERETO AND DIRECTEDTOWARD SAID OPENING TO MOVE SCUM TOWARD SAID OPENING.